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A Blank Solar Disk


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About this observation
Pete Lawrence
Time of observation
24/06/2016 - 15:09
Observing location
Selsey, UK
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NASA has recently noted that the solar disk is unusually free from sunspots, and this week's Picture of the Week, taken on 2016-06-24 has been contributed by Pete Lawrence.  This is indeed the "low point" of the latest solar cycle, but it is unusual to have a completely blank disk.  The other interesting fact which is worth a mention is that although the overall solar radiance (output) varies by only 0.1%, the extreme ultra-violet component can vary between solar minimum and maximum by as much as 10% or more.  Investigations are continuing into what effects this wide variation in high energy radiation might have on our planet. For more on this you can read the NASA article at

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